Members of the upper chamber unanimously adopted a motion to investigate the matter after Senate Speaker Noel Kinsella ruled there appeared to be enough of a case to proceed.
In a question of privilege put to the Senate, Liberal Sen. James Cowan said an alleged attempt by the RCMP to prevent Cpl. Roland Beaulieu from testifying Monday at a committee may amount to serious interference.
The Mounted Police Professional Association of Canada, which represents many regular and civilian Mounties, says the RCMP recently told Beaulieu that if he was well enough to go to Ottawa to testify, he should be fit enough to work.
Rob Creasser, a former RCMP officer and spokesman for the association, says the force had not previously objected to Beaulieu travelling outside his district of duty even though he is on medical leave.
Beaulieu, who is involved with the professional association, did not go to Ottawa — though another representative of the group did testify at the Senate national security and defence committee.
The committee was studying a government bill to revamp the RCMP's disciplinary procedures.
The Senate committee on rules, procedures and the rights of Parliament will probe the Beaulieu case. No hearings had been scheduled as of late Wednesday.
Cowan says he looks forward to seeing what the Senate committee turns up.
"What I do know is that there is a real chill out there," Cowan said Wednesday in an interview.
"We're standing up for not only our rights to hear from witnesses, but more importantly the rights of individuals to come before parliamentary committees without any fear of being intimidated or threatened."
Earlier this week Public Safety Minister Vic Toews said there was no attempt to muzzle Beaulieu and he dismissed the concerns of opposition MPs.
There had been suggestions the RCMP drafted a new policy on travel just last week in order to prevent Beaulieu from coming to Ottawa.
The RCMP said Wednesday that the policy in question has been in place since March 19, 2009, and the copy presented to Beaulieu happened to be stamped May 3, 2012 — the day he received it.
The policy says a member on sick leave must have his commander's written approval to travel beyond the member's duty area for more than 24 hours, excluding travel for personal reasons during regular time off.