Is Friar Laurence blamed for the deaths of Romeo and Juliet? Explain and give some evidences.

Immediately after the deaths of Romeo, Juliet, and Paris,
Friar Lawrence, Prince Escalus considers Friar Lawrence one of the "parties of
suspicion."  Balthsar, who was Romeo's servant and friend, and the "boy" of Count Paris
are also found nearby.

Although Prince Escalus does not
verbalize and accusation of guilt, Friar Lawrence declares that he is "the greatest,
able to do least" regarding the deaths.  He also states that the is there to "impeach
and purge, myself condemned and myself excused."  In other words, he considers himself
guilty, yet innocent; he did play an undeniable role in the tragedies that took place,
but he intended only good (peace between the Montague and Capulet
families).

Friar Lawrence concludes his monologue
recounting the facts of the events that took place by
saying

...and
if aught in this

Miscarried by my fault, let my old
life

Be sacrificed some hour before his
time

        Unto the rigor
of severest law.

The Friar accepts guilt for taking part in
the unsuccessful plan and offers to pay with his life, if
necessary.