difference between "consider" and "consider to"

Hello everyone, 

Is there any difference between the following sentences?  

They considered him a fool.
They considered him to be a fool.   

Similar structure:  
His lawyers proved him innocent.
His lawyers proved him to be innocent.  

I couldn't find any diffrence.  

Thanks in advance.

There are six patterns involving a predicate complement of the object.  The complement can be a noun phrase (NP) or an adjective phrase (AP).

NP V NP NP |   NP V NP AP
NP V NP to be NP |   NP V NP to be AP
NP V NP as NP |   NP V NP as AP

The same verb can often take more than one of these patterns with no change of meaning.  But exactly which pattern(s) each verb can take is a matter of considerable confusion at times!  (Reminder:  * = ungrammatical; ?= borderline grammatical; possibly ungrammatical.)

consider him a fool |  consider him crazy
consider him to be a fool |  consider him to be crazy
?consider him as a fool |  ?consider him as crazy

prove him an innocent man | prove him innocent
prove him to be an innocent man |  prove him to be innocent
*prove him as an innocent man |  *prove him as innocent

appointed/named him secretary | *appointed/named him secretarial
appointed/named him to be secretary |  *appointed/named him to be secretarial
appointed/named him as secretary |  *appointed/named him as secretarial

*knew him an honest man |  *knew him honest
knew him to be an honest man |  knew him to be honest
*knew him as an honest man |  *knew him as honest

*describe/treat him a friend |  *describe/treat him foolish
*describe/treat him to be a friend | *describe/treat him to be foolish
describe/treat him as a friend | describe/treat him as foolish

proclaim him a hero |  ?proclaim him heroic
proclaim him to be a hero |  ?proclaim him to be heroic
*proclaim him as a hero | *proclaim him as heroic

CJ