Whether a Magistrate, who forwarded the private complaint filed before him to the police for investigation under Section 156(3) Cr.P.C. can interfere in the pending investigation by directing the police to add some more sections of offences in the FIR and investigate? - yes - Private complaint under sec.420, 406 r/w 34 and 120 B I.P.C. forward for investigation - Crl.M.P. filed to added additional sections 409 and 477 A I.P.C., and to investigate - Magistrate allowed the petition - their lordships held that Section 2(h) " investigation" includes all the proceedings under this Code for the collection of evidence conducted by a police officer or by any person (other than a Magistrate) who is authorised by a Magistrate in this behalf; - So, the investigation is an exercise conducted by the police or by the person authorised by magistrate to collect the evidence relating to a particular offence.- as held by Apex court It is well-settled that when a power is given to an authority to do something it includes such incidental or implied powers which would ensure the proper doing of that thing - In my considered view, by this order, he has not committed any judicious overreaches and made an impermissible penetration into the domain of investigation. The prerogative of police to investigation has been kept in tact, but they were only asked to investigate whether the accused have in fact committed the offences under the newly added sections including the ones which are already referred. So, the act of Magistrate cannot be found fault with.- 2015 Telagana & A.P. msklawreports

The defacto complainant filed a private compliant against A1 to A3
before I AJMFC, Kothagudem on the allegations that complainant and
accused are employees of Singareni Collieries Company Limited,
Kothagudem  under Sections 420, 406 r/w 34 and 120B
IPC.
The Court referred the complaint to I Town PS, Kothagudem under
Section 156 (3) Cr.P.C. and the police registered a case in Cr.No.443 of
2014 and investigating the case.
 While so, the complainant filed
Crl.M.P.No.8 of 2015 under Section 156 (3) Cr.P.C. requesting the Court to
direct the police to incorporate Sections 409 and 477A IPC in FIR No.443
of 214. 
The accused opposed the petition on the ground that the Court
cannot interfere with the investigation. 
However, the learned Magistrate
turned down the objection and allowed the petition.

Section 156 in The Code Of Criminal Procedure, 1973
156. Police officer' s power to investigate cognizable case.
(1) Any officer in charge of a police station may, without the order of a
Magistrate,
investigate any cognizable case which a Court having jurisdiction over the local
area within the limits of such station would have power to inquire into or try
under
the provisions of Chapter XIII.
(2) No proceeding of a police officer in any such case shall at any stage be
called
in question on the ground that the case was one which such officer was not
empowered under this section to investigate.
(3) Any Magistrate empowered under section 190 may order such an investigation
as
above- mentioned.
a)      Section 156 (3) Cr.P.C. lays down that a Magistrate who is
empowered under Section 190 Cr.P.C. to take cognizance of an offence,
may refer the compliant to police under Section 156(3) Cr.P.C. for
investigation without taking cognizance. This reference is thus a
pre-cognizance reference. In such an instance, the concerned police have
to register the FIR basing on such reference and shall conduct investigation
and file a final report/charge sheet under Section 173(2) Cr.P.C. or file a
referred report. Now, the question is whether during the pendency of
investigation whether a Magistrate can interfere with the registration and
give directions.
        The word investigation is defined under Section 2(h) Cr.P.C. as
follows:
Section 2(h) " investigation" includes all the proceedings under this Code for
the collection of evidence conducted by a police officer or by any person (other
than a Magistrate) who is authorised by a Magistrate in this behalf;

So, the investigation is an exercise conducted by the police or by the person
authorised by magistrate to collect the evidence relating to a particular
offence
The
Apex Court laid down that Magistrate under Section 156(3) Cr.P.C. has
power to monitor investigation to ensure that it is properly done, if the
investigation is not done properly

held thus:
13. We would further clarify that even if an FIR has been registered and even
if
the police has made the investigation, or is actually making the investigation,
which
the aggrieved person feels is not proper, such a person can approach the
Magistrate under Section 156(3) Cr.P.C., and if the Magistrate is satisfied he
can
order a proper investigation and take other suitable steps and pass such order
or
orders as he thinks necessary for ensuring a proper investigation. All these
powers
a Magistrate enjoys under Section 156(3) Cr.P.C.
The Apex Court further observed thus:
 In our opinion Section 156(3) Cr.P.C. is wide enough to include all such
powers in a Magistrate which are necessary for ensuring a proper
investigation, and it includes the power to order registration of an F.I.R. and
of ordering a proper investigation if the Magistrate is satisfied that a proper
investigation has not been done, or is not being done by the police. Section
156(3) Cr.P.C., though briefly worded, in our opinion, is very wide and it
will include all such incidental powers as are necessary for ensuring a
proper investigation.
 It is well-settled that when a power is given to an authority to do
something it includes such incidental or implied powers which would ensure
the proper doing of that thing. In other words, when any power is expressly
granted by the statute, there is impliedly included in the grant, even without
special mention, every power and every control the denial of which would
render the grant itself ineffective. Thus where an Act confers jurisdiction it
impliedly also grants the power of doing all such acts or employ such means
as are essentially necessary to its execution.
The reason for the rule (doctrine of implied power) is quite apparent.
Many matters of minor details are omitted from legislation. As Crawford
observes in his 'Statutory Construction' (3rd edn. page 267):
If these details could not be inserted by implication, the drafting of
legislation would be an indeterminable process and the legislative intent
would likely be defeated by a most insignificant omission.
x x x x x
In view of the abovementioned legal position, we are of the view that
although Section 156(3) is very briefly worded, there is an implied power in
the Magistrate under Section 156(3) Cr.P.C. to order registration of a
criminal offence and/or to direct the officer in charge of the concerned police
station to hold a proper investigation and take all such necessary steps that
may be necessary for ensuring a proper investigation including monitoring
the same. Even though these powers have not been expressly mentioned in 
Section 156(3) Cr.P.C., we are of the opinion that they are implied in the
above provision.
           So, a perusal of the above decision would show that for ensuring
proper investigation the Magistrate has power to monitor the investigation
under Section 156(3) Cr.P.C. However, such a power has to be exercised
cautiously and with judicious discretion.
 Now, coming to the instant case, the Magistrate under the impugned
order directed the police to add Sections 409 and 477A IPC to the FIR and
investigate and file the report.  In my considered view, by this order, he has
not committed any judicious overreaches and made an impermissible 
penetration into the domain of investigation. The prerogative of police to
investigation has been kept in tact, but they were only asked to investigate
whether the accused have in fact committed the offences under the newly
added sections including the ones which are already referred. So, the act of
Magistrate cannot be found fault with.- 2015 Telagana & A.P. msklawreports